Re: Novice question, conservation of energy

On Aug 15, 6:01 am, nsa....@xxxxxxxxx wrote:
Hi,

This may be naive but if you were to split a laser-beam with a
beamsplitter and then point the two beams directly at each other (with
one beam phaseshifted to 180 degree opposite) then would the beams
cancel each other out?
If so, where does the energy go since it can not be destroyed...?

If the beams are directed at each other, the phase shift will vary
along the direction of the beams. It will be 180 degrees in some
locations, 0 degrees in other locations, and other values elsewhere.

In short, total energy is still conserved.

Second question, can two laserbeams be combined to form a single third
beam that is exactly equal in energy (minus any minor heat deposited
on reflective surfaces etc) to the two original beams? If not, is
there some fundamental law against this?

Yes, it's possible (in principle) with a good 50/50 beamsplitter.

Thanks!
Tobias

You're welcome,

Mark

.

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